Yes there is a command for checking if the client is working properly. The command is /opt/quest/bin/vastool status.
Please read How to monitor the health of the Authentication Services client?
You can also setup the command to be run automatically through the Management Console for Unix (MCU) to monitor the clients. Please see the Management Console for Unix guide which is in the doc folder of the download or available for download on our support portal for further information about this task.